WASHINGTON—Nearly a year after the U.S. Department of Defense decided to enforce a “Buy American” directive for military athletic shoe purchases, American athletic footwear manufacturers are waiting for the Pentagon's final approvals.

“We are patient and optimistic,” said a spokeswoman for Boston-based New Balance Athletic Shoe Inc. “We know it's going to be a long process.”

The “Buy American” mandate originates from the Berry Amendment, a law passed in the 1940s that directs DOD to buy all military clothing and shoes from domestic manufacturers.

DOD, however, long insisted that domestically made running shoes were inferior to those manufactured abroad. This meant that U.S.-based athletic footwear manufacturers such as New Balance and Big Rapids, Mich.-based Wolverine Worldwide (owner of the Saucony athletic footwear brand) were losing out on supplying the military an estimated 250,000 pairs of running shoes annually.

More than two years ago, shoe manufacturers began to negotiate with the Pentagon, New England members of Congress, including Maine Sens. Angus King (I) and Susan Collins (R), Massachusetts Democratic Rep. Niki Tsongas and then-Maine Democratic Rep. Mike Michaud. They aided the footwear makers, even offering to introduce legislation to force DOD to buy domestic athletic shoes.

Christine Fox, acting deputy secretary of defense, wrote Michaud on April 25, 2014, telling him that DOD would modify its standing allowance system for military recruits to buy their own athletic shoes.

“As Berry Amendment-compliant shoes come on the market, we will assess them for cost and durability to ensure they are comparable to other models available to recruits,” Fox wrote. “If one or more comparable Berry Amendment-compliant shoe models correspond to a shoe type category, only these shoes will be made available for purchase using the one-time cash allowance.”

DOD asked interested manufacturers to submit shoes for testing as a prerequisite for certification under the Berry Amendment.

New Balance submitted three pairs of shoes for testing at the U.S. Army installation at Fort Jackson, S.C., and testing began in January, the New Balance spokeswoman said.

A Wolverine spokesman said his company is working closely with DOD as the agency continues to develop its testing protocol.

100 percent American-made

One of the most difficult aspects of complying with the Berry Amendment, the shoe manufacturers said, was ensuring their products met its requirements on content.

“We have a very broad supplier base,” the New Balance spokeswoman said. “The big issue was having our suppliers certified as providing components that were 100 percent made in America. But everyone was willing to help, and everyone supports this.”

As part of its effort to gain 100 percent American content, New Balance installed a machine to fabricate midsoles at its Boston facility last year, she said.

Wolverine is able to source all components domestically for its Saucony and other athletic shoe brands, according to its spokesman. “We have worked with the U.S. industrial base to support this initiative and to fine-tune components for athletic footwear production.”

Last year, Wolverine opened a new production line for its Saucony line in Big Rapids, the spokesman said. Those shoes will start being produced sometime this year, he said.

While he declined to reveal the initial new capacity at Big Rapids, he did say that all of the new production initially will go to the Armed Forces, with some later production slated to go to commercial markets.

While Concord, Mass.-based Vibram U.S.A. is not a manufacturer of finished shoes, it has produced shoe soles in the U.S. since 1964 in partnership with North Brookfield, Mass.-based Quabaug Corp.

In response to the DOD's new Buy American policy, Vibram and Quabaug announced last year they would jointly invest $1.2 million in innovation and technology.

Separate from that investment, Vibram and Quabaug also announced joint research in technologies to co-mold rubber with ethylene vinyl acetate, the material that comprises midsoles in most athletic footwear.

Vibram and Quabaug are working with Werthern Industries, an adhesive supplier, to commercialize the co-molding process, according to Bill Ells, Vibram U.S.A. vice president of sales and marketing.

“The production methods of co-molding have required a change in both the production process and machinery,” Ells said.

Vibram, Quabaug and Werthern have developed a combined soling unit comprised of an injection-molded midsole and Quabaug-produced rubber outsole, he said. The companies are evaluating equipment options, with the goal of adding capacity in 2015, he said.

Ells said his company didn't anticipate seeing any significant effects on its production from the Berry Amendment until the second quarter of this year.

Vibram, Quabaug, New Balance and Wolverine expressed optimism regarding the effects of the Berry Amendment on their businesses.